Traffic control system



June 23, 1942. B. COOPER TRAFFIC CONTROL SYSTEM Filed Feb. 21, 1940 2Sheets-Sheet l INVENTOR fiI/VJAM/N COOAE'R ATTUINEY June 23, 1942. B.COOPER TRAFFIC CONTROL SYSTEM Filed Feb. 21, 1940 2 Sheets-Sheet 2 B99699 99 F IG 3 INVENTOR EE'JVJAM/N COOPER BY ATTORNEY Patented June 23,1942 UNITED STATES PATENT OFFICE 2,287,090 TRAFFIC coN'mor. SYSTEMBenjamin Cooper, Jersey City, N. J.

Application February 21, 1940, Serial No. 320,020

36 Claims.

This invention relates to traihc control systems.

In highways, bridges, tunnels, and the like arteries for vehiculartraflic, particularly where there is only one lane for each direction ofvehicular travel, any obstruction to the flow of traflic, or slowingdown of traflic below a predetermined speed, as may be caused by avehicle stalling in the roadway, will result in blocking tramc anddelay. If the normal movement of traflic is not restored quickly, aserious tie-up may follow. In highway tunnels, where traffic is notvisible from the outside, a group of oflicers are usuailly maintained tocontinually patrol the highway within the tunnel and report to a traflicsupervisor any obstruction in the lane or speeding violations, so thatthe necessary action may be immediately taken to clear the highway orapprehend the violators. These methods of traffic supervision areexpensive and relatively slow. It is an object of this inventiontherefore to provide an automatic trafllc control system which willautomatically detect an interruption in the flow of trafiic anywherealong the highway, and operate a warning signal located outside of thetunnel or at any point remote from the roadway, to indicate that traflichas been held up.

It is a further object of this invention to provide, in a trafliccontrol system of the character described, automatic means fordetermining the approximate location of the obstruction on the highwayand indicating said location on a supervisory panel located at anyconvenient point, remote from the highway.

It is still a further object of this invention to provide in a traflicsupervisory system of the character described, means for regulatingtraffic lights disposed along the highway so that when traffic is heldup, all the lights before the obstructed area turn red, whereas thelights after the obstruction are green. Thus, vehicles moving toward theobstructed area are stopped, preventing a traffic jam, whereas vehiclesmoving away from said area are permitted to continue.

In ,traflic lanes, curves become points of danger. When vehiclestraversing these lanes pass these points at greater speeds than isordinarily safe. the possibility of accidents resulting is great. It istherefore 'a still further object of this invention to provide means tocaution drivers whenthey are exceeding safe speeds over a section of alane of a highway, and to further provide means to indicate on a remotepanel in which section of a lane vehicles are being driven at excessivespeed.

Still another object of this invention is to provide a trafficsupervisory system of the character described which shall be relativelyinexpensive to manufacture, positive in operation, and yet practical andefflcient to a high degree in use.

Other objects of this invention will in part be obvious and in part behereinafter pointed out.

The invention accordingly consists in features of construction,combination of elements, and arrangement of parts which will beexemplifled in the construction hereinafter described, and of which thescope of application will be indicated in the following claims.

In the accompanying drawings:

Fig. 1 illustrates a schematic drawing of the trafilc control circuitembodying the invention;

Fig. 2 is a front view of a differential counter used in connection withsaid circuit; and

Fig. 3 represents a supervisory panel upon which the warning signal andindicating devices may be located.

Referring now to the drawings, the traflic control system embodying theinvention comprises a plurality of vehicle treadles such as H, l2, l3,l4 and I5, Fig. l, disposed at spaced intervals along a lane of ahighway, traversely thereof. The treadles may be of any suitable typeadapted to close a switch when actuated by a vehicle passing thereover,and may, comprise pairs of top and bottom contact strips such as Ila'llb; l2a-l2b; etc., normally spaced apart but adapted to be pressedtogether for closing an electrical circuit when the wheels of a vehiclepass over the treadle. The sections of highway bounded by successivetreadles are designated in the drawings as sections A, B, C, and D;section A being located between treadles H and 12, section B lyingbetween treadles I2 and I3, etc. Said highway sections have associatedtherewith similar differential counters All), Bill, CHI and DH,respectively, one of which is shown in detail in Fig. 2 of the drawings.

Referring now to Fig. 2, each counter comprises a vertical mountingpanel 20 having rotatably mounted thereon and disposed in the samevertical plane two pairs of similar, vertically aligned sprocket wheels2|, 23 and 22, 2|. Connecting wheels 2| and 23 is an endless link chain25, the links thereof meshing with the sprockets of said wheels. Thewheels 22 and 24 are similarly connected by an endless chain 26.

Floatingly supported on end between the chains wise direction, lookingat Fig. 2 of'the drawings, I

chain 25 moves wheel 21 upwardly and raises rod 29. When wheel 22 isrotated counter-clockwisely wheel 21 and rod 29 are moved downwardly.

Means is provided to move the rod 29 of the corresponding differentialcounter upwardly a predetermined distance each time a vehicle axle entera particular section of highway, and to move said rod downwardly anequal distance each time a vehicle leaves said highway section, so thatthe vertical position of rod 28 will continuously indicate the number ofvehicle axles within saidhighway section.

To this end, there is mounted on wall 29, above the wheel 2|, ahorizontal electromagnet 3| having a U-shaped core 32 comprisingparallel upper and lower horizontal legs 33 and 34. Surrounding leg 34is a coil 35. Pivoted to the end of leg 33 and extending downwardlytherefrom adjacent the leg 34 is an armature 36 normally urged in aclockwise direction against a stop.39 by a coil tension spring 31.Pivotally connected to the bottom end of armature 39, as at 39a, is apawl 39. Rigidly attached to the sprocket wheel 2| and concentrictherewith is a ratchet wheel 49 contacted by the pawl 39. A coil tensionspring 4|, connected between said pawl 39 and the armature 36, tensionssaid pawl into engagement with the ratchet 49.

Each time the coil 35 is energized the arma ture 39 is attractedcounter-clockwisely moving the pawl 39 to the right and advancing wheel2| a predetermined angle in a counter-clockwise direction. Wheel 21 androd 29 are consequently raised a predetermined distance.

The sprocket wheel 22 is similarly controlled by an electromagnet 42having a coil 43 and a pawl 44 contacting a ratchet wheel 45 on wheel22. Ratchet45 is similar to ratchet 49 so that wheels 2| and 22 areadvanced equal angular distances for each actuation of their respectiveelectromagnet. Hence each energization of the coil 43 lowers rod 29 byan amount equal to the distance said rod is raised when coil 35 isenergized.

The coils 35 corresponding to the counters A|9, Bl9, CIO and D|9 aredesignated as A35, B35, C35 and D35, respectively; and the coils 43 ofsaid counters are designated as A43, B43, C43, respectively. Referringto Fig. 1, one end of the coils A35, B35, C35 and D35 are connected tothe negative power supply through the treadle switches ll, l2, l3 andi4, respectively, the other a succeeding section, the coil A43, B43, C43or D43 corresponding to said section from which the vehicle is exiting,is energized, for lowering the respective rod 23 and indicating that avehicle axle has left said section. Furthermore, the coil A35, B35, C orD35, corresponding to the succeeding highway section into which thevehicle is entering is simultaneously energized for raising the rod 29corresponding to said succeeding section, and indicating that anadditional axle has entered said section.

The counters Al9, BIO, CI9 and D|9 may be mounted together on the backside of a supervisory control panel such as panel 49, of Fig. 3. Saidpanel is formed with a plurality of slots 41 through which the rods 29-are visible. Said rods 29 may be provided with an indicating mark suchas thecolored section 49, by means of which the vertical position of therods can:

be determined by glancing at the front of the panel. Furthermore, ascale calibrated in units of vehicle axles may be mounted on the frontof said panel adjacent to slots 41 so that an observer can immediatelydetermine the density of traffic in any section.

There are also mounted on the supervisory panel 45, incidating lampsA59, B59 and C59, corresponding respectively to the highway sections A,B and C. Means is provided to illuminate the lamps corresponding to thevarious sections when the flow of traflic in said sections is obstructedby a stalled car in the roadway.

To this end the counters Al9, Bl9, C|9 and D|9 are provided with contactarms A59, B59, C59 and D59, mounted on the respective panels 29 beneaththe rods 29. Arms A59 and C59 are connected to negative power supply andthe arms B59 and D59 are connected to the positive power supply, Fig, 1.Said contact arms are' adapted to be contacted and moved downwardly bythe insulating studs 29a when the respective rods 23 are in bottomposition, corresponding to the condition that there are no vehicles inthe respective highway section.

Arm A59 is normally open but is moved into engagement with a fixedcontact A5| when the corresponding rod 29 is raised by the presence ofone or more vehicle axles in section A.

The arm B59 normally engages a fixed contact B52 but is moved awaytherefrom and into engagement with the fixed contact B5l when there arevehicle axles in section B.

The arm C59 similarly engages a fixed contact C52 but is moved intoengagement with the fixed contact C5| when the rod 29 of counter CM israised from its bottom position.

The arm D59 normally engages fixed contact D52 when the highway sectionD is vacant, but is moved away therefrom when the corresponding rod 29is raised by the presence of vehicle axles in section D.

There are further provided three similar relays A53, B53 and C53,corresponding respectively to the sections A, B and C. Said relays maybe of any suitable time delayed type, constructed so that the respectivecontact arms are not actuated until the coil has been energized for apredetermined time interval. If the coil is energized and thende-energized before the predetermined time interval has elapsed, therelay becomes reset and the coil must be re-energized for the completetime interval before the contact arms are actuated. Relays of this typeare old in the art.

Relay A53 has an actuating coil A54 and controls two normally opencontact arms A55 and A51 which move into engagement with the fixedcontacts A56 and A56 when said relay is actuated. Relay B53 has a coilB54 and also controls 'two normally open contact arms B55 and B51 whichengage the fixed contacts B56 and B55 when said relay is energized.Similarly relay C53 has a coil C54 and moves normally open contact armsC55 and C51 into engagement with the contact C56 and C56 when said relayis energized.

The coils A54, B54 and C54 have one end thereof connected by wires A65,B60 and C60 to fixed contact A5l, BH and CH, respectively, of thecorresponding differential counters. The other ends of said coils areconnected by wires A6 I, B6! and C6! to the fixed contacts B52, C52 andD52, respectively, the differential counter of the next succeedinghighway section. The contact arms A55, A51, B55, B51, and C55, C51 areconnected to the negative power supply.

The indicating lamps A59, B59 and C59 have one terminal thereofconnected to the positive power supply and have their other terminalsconnected to the fixed contacts A56 and C56, respectively.

When a vehicle axle enters a highway section such as B, thecorresponding rod 26 is raised permitting contact arm B50 to engagefixed con- Ii there are no vehicle axles in the next succeeding sectionthe arm C50 is in engagement with the contact C52, as heretoforedescribed. A circuit is thus completed through coil B54 of relay B53,traceable from positive power supply, arm B50, contact Bl, wire B60,coil B54, wire BSI, contact C52, contact C50, to negative power supply.The time delay of relay B53 is pre-set for a time interval slightly inexcess of I the normal time required for a vehicle to traverse thesection B. Thus, if the vehicle continues along at the normal rate ofspeed it will enter section C and actuate counter Cl0 for raising therod 29 before relay B53 has had sufiicient time to become actuated. Thecontact arm C50 will thereupon move out of engagement with the contactC52 and open the above mentioned circuit for the relay B53. The timedelay of said relay is thereupon reset to zero pending reactuation by asubsequent vehicle axle.

However. if a vehicle should remain in section B longer than the timedelay of B53, as for example because of a vehicle breakdown or accident,contact arm B50 will remain in engagement with the arm B5l. The vehiclesfollowing the stalled car would have to stop since the lane is blocked.However, the vehicles ahead of the obstructedsection can continue tomove until there are no vehicles in the section C. Thus, the coni tactarm C50 will move into engagement with the contact C52 and will remainengaged therewith until the obstruction has been cleared for permittingvehicles to move again over the highway lane. The relay B53 is thereuponenergized as heretofore described, and will remain energized until theflow of trafilc is restored. After the necessary time delay interval ofrelay B53 has elapsed, the contact arms B55, B51 will move intoengagement with the fixed contacts B56, B55. The lamp B59 is thereuponenergized through a circuit from negative power supply, arm B51, contactB56. lamp B59, to positive power supply.

Since the lamp B59 is located on the supervisory control panel, whenlamp B59 becomes illuminated the trafilc supervisory personnel areimmediately informed that the section B of the highway is blocked andthe necessary steps may be taken to clear the obstructed section.

Means is also provided to actuate a warning signal, herein illustratedas a bell W, when any of the indicating lamps are illuminated, toimmediately attract the attention of the supervisory personnel when thehighway becomes blocked.

Tothis end there are provided three secondary relays A63, B63 and C63corresponding to the relays A53. B53 and C53, respectively.

Relay A63 has an actuating coil A62 and controls two contact arms A64,A66. The arm A64 is normally open whereas arm A66 normally engages afixed contact A10. When said relay A63 is energized arm A64 is movedinto engagement with a fixed contact A61 and arm A66 is moved intoengagement with a fixed contact A69 The relay B63 has an actuating coilB62 and controls three switch arms B64, B and B66 of which the arms B64and B65 are normally open whereas arm B66 normally engages fixed contactB10. When said relay B63 is energized the arms B64 and B66 are movedinto engagement with fixed contacts B61 and B68, and arm B66 is movedout of engagement with contact B10 and into engagement with contact B69.

The relay C63 similarly has a coil C62 and controls three switch armsC64, C65 and C66 of which arms C64 and C65 are normally open whereas armC66 normally engages the fixed contact C10. When relay C63 is energizedthe arms C64, C65 and C66 move into engagement with the fixed contactsC61, C68 and C69, respectively.

Coils A62, B62 and C62 have one end thereof connected to the positivepower supply and their other ends are connected'by wires All, B1! andC1! to the fixed contacts A56, B56 and C56, re-

spectively, of the relays A53, B53 and C53. It is seen that when any ofthe time delayed relays, such as relay B53, is actuated thecorresponding secondary relay, such as relay B63, is energized through acircuit from negative power supply, arm B55, contact B56, wire B1l, coilB62, to positive power supply.

One end of the actuating coil Wi of bell W, is connected to positivepower supply and the other end of said coil is connected by wires A12,B12 and C12 to the fixed contacts A61, B61 and 061, respectively. It isseen that when any secondary relay A63, B63 and C63 is energized thewarning bell W is actuated through a circuit from positive power supply,coil Wl, switch arm A64, B64 or C64 to negative power supply. Thus, whenany indicating lamp A59, B59 or C59 is illuminated, the warning bell Wis simultaneously energized, for attracting attention to the fact thatthe highway is blocked.

Disposed along the highway are traffic signal lights A15, B15 and C15,preferably located adjacent the corresponding treadles Ii, l2 and I3,respectively. Said signals comprise red lights A16, B16 and C16 andgreen lights A11, B11 and C11, respectively.

The lamps A16 and A11 have one end thereof connected together and topositive power supply. The other end of lamp A16 is connected by wireA10 to the fixed contact A69 and the other terminal of lamp A11 isconnected to the fixed contact A10 by wire A19.

Similarly, the lamps B16 and B11 have one end thereof connected by wiresB19 and B19 to the fixed contacts B69 and B10, respectively, whereas theother end of said lamps are connected together and to positive powersupply. The lamps C16 and C11 also have one end connected to positivepower supply whereas their other ends are connected by wires C16 and C19to the fixed contacts C69 and C10, respectively.

It will now be understood that the green lights A11, B11 and C11 arenormally illuminated, the circuit for light A11 being traceable fromnegative power supply, arm A88, contact A18, wire A19, light A11, topositive power supply. Similarly, the circuits for lights B11, C11involve switches B88, B18 and C88, C18, respectively.

However, when any secondary relay becomes energized, as heretoforedescribed, by reason of the obstruction of trafllc in the correspondinghighway section, the corresponding arm A88, B88 or C88 is 'moved out ofengagement with the respective contact A18, B18 or C198, and intoengagement with the contacts A89, B89 or C89.

- Thus, the corresponding green traflie light is extinguished, and thered light is stopped under the direction of said red light, preventing atrafilc jam in said section.

Means is also provided to change the green lights of all sectionslocated before the obstructed section to red. To this end the fixedcontact C88 is connected by wires C88 and B" to the coil B82 and contactB88 is connected by wire B88 and A" to the coil A82. When the secondaryrelay C88 is energized a circuit is completed for energization of coilB82 traceable from negative power supply, contact arm C88, contact C88,wire,

C88, wire B1l, coil B82, to positive power supply. Similarly, when relayB88 becomes energized, a circuit for 'energization of coil A82 iscompleted from negativepower supply, contact arm B88, contact B88, wireB88, wire A1l, coil'A82 to positive power supply. It is thus seen thatwhen any secondary relay is energized all the second-, ary relays priorto said energized relay will be successively actuated. Consequently allthe green lights located beforev the obstructed section will be changedto red, whereas the traiiic lights of succeeding highway remain green.

It is understood that as many highway sections as desired may beincluded in the supervisory system described herein. Each additionalhighway section requires an additional treadle, differential counter,time delayed relay, secondary relay and trafiic lights. Said additionalequipment is connected into the circuit in a manner similar to thesection B of Fig. l.

It will also be understood that instead of usin a single contact treadleas shown in Fla. 1, a uni-directional multi-contact treadle may be usedsuch as is described in my co-pending application Serial No. 34,525filed August 3, 1935. In such case the counter F of said co-pendingapplication is replaced by a relay controlling an additional normallyopen switch replacing the treadle of this application. Thus a vehicletraversing the highwayin one direction will close said additional switchand actuate the differenplish this purpose there are provided signalsB8l,- C8l etc., associated with the sections B, C etc. Said signal maybe in the form of a caution light or any other suitable warning device.There is no caution light in the front section A. On the control panelare indicating devices B99, C99 etc. located adjacent the differentialcounter Bl8, Cl8 ;etc., there being none adjacent counter Al8.

Associated with the differential counters Al8. Bl8,Cl8etc.,are switcharmsAl l8,Bl l8'andCll8 etc. respectively. These switch arms areconnected by wires All2, Bll2, CH2 etc. to the treadle switch contactsllb, I21), I81) etc., respectively. The switch arms All8, Bll8, and

Cl l8 etc. are adapted to be held by the rods A28 of dififerentialcounters .Al8, Bl8, Cl8 etc. in engagement with fixed contacts Al I l,Bl II and Clll etc. until the rods are raised by passage of at leasttwo. cars into the sections associated with said respective counters.

Associated with the counters Al8, Bl8 and C" etc. are relays A88, B88,C88 etc. Said relays are provided with coils A88, B88, C88 etc.respectively, connected to the fixed contacts All I, Blll, Clll etc. Therelays A88, B88, C88 etc. are adapted to move normally open switch armsA88, B88,'C88 etc; into engagement with fixed contacts A88, B88, C88etc. respectively. The switch arms A88, B88 and 088 etc., are connectedto the minus power supply.

Associated with the differential counters A", Bill and C18 etc., arefast closing, slow opening time delay relays -A81, B81, C81 etc.respectively, provided with coils A88, B88, C88 etc., connected to thefixed contacts A88, B88 and C88 etc. respectively, at one side,.and eachconnected to the plus power supply at the other side. The relays A81,B81, C81 etc. are adapted to move switch arms A89, B89 and C89 etc.which are normally in engagement with fixed contacts A98, B98 and C98etc. respectively, out of engagement with respect to said fixedcontacts. Said switch arms are connected to the pluspower supply. Therelays A81, B81 and C81 are also adapted to move normally open switcharms A9l, B9l and C9l etc., into engagement with fixed contacts A92,

tial counter. A vehicle traversing the highway in the opposite directionwill not energize said relay and will produce no effect on thesupervisory system.

The use of uni-directional treadles in the circuit disclosed in thisapplication is sometimes necessary in highways where vehicle drivers maytraverse the dividing line between lanes carrying trafllc in oppositedirections, and actuate a treadle in the opposite lane. With theunidirectional treadle this will have no efiect on the operation of thesupervisory system of said opposit lane.

Means is also provided to caution operators driving vehicles along thelane at an excessive speed, and also to indicate on the control panel"where the speeding is taking place. To accom- B92 and C92 etc.respectively. The coils A88, B88 and C88 etc. of the relays A88, B88 andC88 etc respectively are connected by wires All8, Bll8 and CH8 etc. tothe fixed contacts'A98, B98 and C98 etc. respectively.

Associated with the differential counters Al8, Bl8 and Cl8 etc. 'arerelays A98, B98, C98 etc. having coils A98, B98 and C98 etc.respectively. Said coils are connected by wires All8, Bll8, CH8 etc. tothe treadle switch contacts 12b, I81) and Nb etc. respectively, of theswitches l2, l8, l8 etc. The other sides of the coils A98, B98, C98 areconnected by wires All5, B lli, CH5 etc., to the fixed contacts A92, B92and C92 etc. respectively. The relays A93, B98, C98 are adapted to movenormally open switch arms A95, B95, C95 etc., which are connected to theminus power supply, into engagement with fixed contacts A98, B98, C98etc. respectively.

The fixed contacts A98, B98 and C98 are connected to warning signaldevices A8l, B8l, Clil etc. disposed in the sections B, C, D etc., saidwarning signals being connected to the plus power supply. The relaysA98, B98, C98 etc. are also adapted to move normally open switch armsA91, B91, C91 etc. which are connected to the Imnus power supply, intoengagement with fixed contacts A98, B98 and C98 etc. Said fixed contactsare connected to indicating devices 1399, C99, D99 etc. which arepreferably mounted on the control panel 99 and located adjacent thediiferential counters Bil, Cll, Dill etc. respectively. The relays A93,B99, C99 etc. are quick closing, slow opening time delay relays, for thepurpose hereinafter appearing.

When a vehicle is the first to enter a given section such as A, relayAll is energized, receiving current from the negative power supplythrough treadle H, movable contact arm All9. fixed contact AIH, coilA99, fixed contact A99, movable contact arm. A99 to the positive of thepower supply.

Energization of relay All moves movable contact arm A99 into contactwith fixed contact A99 and completes a circuit from negative powersupply to arm A95, contact A99 through coil All of relay A91 to positivepower supply, thus energizing said relay 91.

Energization of relay A91 starts the timing process for the firstvehicle of the group that had entered section A. Contact A99 is movedout of engagement with contact A99, and so prevents relay All from beingagain energized when relay A91 is in holding position. Movable arm AM ismoved into contact with fixed contact A92, providing a circuit throughwhich time delay relay B99 will be energized if relay A91 has notreleased contact arm A91.

If the vehicle reaches treadle B after the predetermined time of relayA91, he has not exceeded the fixed speed limit, and so relay A99 cannotbe actuated. If however he has exceeded the speed limit, relay A99 willbe actuated, receiving current from the negative of the power supplythrough treadle l2, coil A94 of relay A99, fixed contact A92, movablecontact A9I to the positive of the power supply.

Energization of relay A99, brings moveable contact arms A95, A91 intocontact with fixed contacts A99, A99, and so closes a circuit throughthe caution light Bll, from negative of power supply to contact arm A99,contact A99, light PM to the positive. This operation also closes acircuit through B99 on the panel 99 from the negative of the powersupply to contact arm A91, contact A99, and light B99 to the positive ofthe power supply.

The same operation takes place in succeeding sections as describedabove.

It will thus be seen that there is provided a device in which theseveral objects of this invention are achieved and which is well adaptedto meet the conditions of practical use.

As -various possible embodiments might be made of the above invention,and as various changes might be made in the embodiment above set forth,it is to be understood that all matter herein described or shown in theaccompanying drawings is to be interpreted as illustrative and not in alimiting sense.

Having thus described my invention, I claim as new and desire to secureby Letters Patent:

1. In an automatic trafllc system, a plurality of vehicle actuatedswitches disposed at spaced intervals along the lane of a highway,dividing said highway into a plurality of sections, an electricallyoperated warning device, and means controlled by said vehicle actuatedswitches, and in-' cluding a circuit for said device and said switches,to energize said warning device when a vehicle traversing the highwaypasses the enterin switch of any section and remains within said sectionlonger than a predetermined period of time, during which period novehicles cross the exit switch oi said section, and all vehicles whichhave crossed the exit switch of said section into the succeedingsection, have left said succeeding section by passing over the exitswitch thereof prior to the beginning of said period, whereby saiddevice indicates that trafilc through said first section is obstructed.

2. In a traflic control system, a plurality of vehicle actuated switchesdisposed at spaced intervals along the lane of a highway, dividing saidhighway into a plurality of successive sections, a plurality ofelectrically operated indicating devices, one for each section, andmeans controlled by said vehicle actuated switches, and including acircuit for said devices and said switches, to operate one of saidindicating devices when a vehicle traversing the highway crosses theentering switch of the section corresponding .to said device and remainsin said section longer than a predetermined period of time after any vehicles which have traversed the exit switch of said section and movedinto the succeeding section have left said succeeding section bycrossing the exit switch thereof.

3. In a traffic system, a plurality of vehicle actuated switchesdisposed at spaced intervals along the lane of a highway, dividing saidhighway into a plurality of successive sections, a plurality ofelectrically operated indicating devices, one for each section, andmeans controlled by said vehicle actuated switches, and including acircuit for said devices and said switches, to operate one of saidindicating devices when a vehicle traversing the highway crosses theentering switch of the section corresponding to said indicating deviceand remains in said section longer than a predetermined period of timeafter any vehicles which have traversed the exit switch of said sectionand moved into the succeeding section have left said succeeding sectionby crossing the exit switch thereof, a warning device, and meansincluded in said circuit for actuating said warning device when any ofsaid indicating devices have become actuated.

4. In a trafllc supervisory system, a plurality of vehicle actuatedtreadles disposed at spaced intervals along the lane of a highway,dividing said highway into a plurality of successive sections, aplurality of electrically operated indicating devices, one for eachsection, and means controlled by said vehicle actuated treadles, andincluding a circuit for said devices and said treadles to operate one ofsaid devices when a vehicle traversing the highway crosses the enteringtreadle of the section corresponding to said device and remains in saidsection longer than a predetermined period of time after any vehicleswhich have traversed the exit treadle of said section and moved into thesucceeding section have left said succeeding section by crossing theexit treadle thereof, stop" trafilc signal means associated with aplurality of said sections, and means included in said circuit to causethe tramc signal means associated with all sections preceding saidsucceeding section to indiczgg stop when said indicating device is actua5. In a tramc supervisory system, a plurality of vehicle actuatedtreadles disposed at spaced intervals along the lane of a highway,dividing said highway into a plurality of successivesections, aplurality of electrically operated indicating devices, one for eachsection, and means controlled by said vehicle actuated treadles, and

including a circuit for said devices and said treadles, to operate oneof said devices when a vehicle traversing the highway crosses theentering treadle of the section corresponding to said .dicate stop" whensaid indicating device is actuated.

6. In a trafllc control system, a plurality of vehicle actuated treadlesdisposed,at spaced intervals along the lane of a highway dividing saidhighway into a plurality of successive sections, a diflerential counterfor each section, means, including a circuit for said treadles and saidcounters, controlled by the treadles bounding any section for countingon the corresponding differential counter the vehicle axles within saidsection at any instant, an electrically operated indicating device foreach section, and means controlled by said counters for actuating saidindicating device when the counter of the corresponding sectionindicates that there has been one or more vehicle axles in said sectionfor a predetermined period of time, while during said period therehas'been no vehicle axles in the next succeeding section.

'1. In a trafllc control system, a plurality of vehicle actuatedtreadles disposed at spaced intervals along the lane of a highwaydividing the highway into a plurality of successive sections, adifl'erential counter associated with each section, means, including acircuit for said treadles and said counters, controlled by the treadlesbounding any section for counting on the corresponding diiferentialcounter the vehicle axles within said section at any instant, anelectrically operated warning device, means controlled by said countersfor actuating said warning device when the counter of any sectionindicates that there have been one or more vehicle axles in said sectionfor a predetermined period of time while during said period there hasbeen no vehicle axles in the next succeeding section.

8. In combination, a plurality of vehicle actuated treadles, disposed atspaced intervals along the lane of a highway, dividing said highway intoa plurality of successive sections, stop traillc signal means associatedwith the plurality of said sections, means, including an electriccircuit for said treadles and said signal means, to cause the trafiicsignal means associated with any section and all preceding sections toindicate "stop" when a vehicle traversing the highway passes theentering treadle of said section and remains in said section longer thana predetermined period of time during which no vehicle passes the exittreadle of said section and all vehicles which have passed the exittreadle of said section into said succeeding section have left saidsucceeding section by passing over the exit treadle thereof prior to thebeginning of said period.

9. In combination with a plurality of vehicle actuated treadles disposedat spaced intervals along the lane of a highway dividing said highwayinto a plurality of successive sections, a plurality of stop" and "go"trafiic signals associated with a plurality of said sections, saidsignals all being normally set for "go," means, including an electriccircuit for said treadles and said signal means, to cause the signalmeans associated with any section and all preceding sections to indicatestop" when a vehicle traversing the highway passes the entering thesdleof said section and remains in said section longer than a predeterminedperiod of time during which no vehicle passes the exit treadle of saidsection and all vehicles which have passed the exit treadle of saidsection into said succeeding section have left said succeeding sectionby passing over the exit treadle thereof prior to the beginning of saidperiod, means, included in said circuit to also cause the trafllcsignals associated with all treadles preceding said section to changefrom "go to stop," whereas the signals succeeding said section remainset for go."'

10. In a trafllc control system, a plurality of vehicle actuatedswitches disposed at spaced intervals along the lane of a highway,dividing said highway into a plurality of successive sections, a controlpanel, a plurality 01' indicating devices one for each section, mountedthereon, and means controlled by said vehicle actuated switches, andincluding a circuit for said switches and said devices, to operate oneof said devices when a vehicle traversing the highway crosses theentering switch of the section corresponding to said device and remainsin said section longer than a predetermined period of time after anyvehicles which have traversed the exit switch of said section and movedinto the succeeding section have left said succeeding section bycrossing the exit switch thereof.

11. In a traiiic control system, a plurality of vehicle actuatedswitches disposed at spaced intervals along the lane of a highway,dividing said highway into a plurality of successive sections, aplurality of electrically operated indicating devices, one for eachsection, and means controlled by saidsvehicle actuated switches, andincluding a circuit for said switches and said indicating devices, tooperate one of said indicating devices when a vehicle traversing thehighway crosses the entering switch of the section corresponding to saiddevice and remains in said section longer than a. predetermined periodoi time after any vehicles which have traversed the exit switch of saidsection and moved into the succeeding section have left said succeedingsection by crossing the exit switch thereof, all of said indicatingdevices being located in juxtaposition so that they may all be seen atonce.

12. 'In combination with means, located at spaced points along a trafficlane, and dividing said lane into a series of contiguous zones, andresponsive to vehicular movement along said lane, electric means locatedat a central station controlled by said first means for indicating inwhich of said zones speed of vehicular tramc is below a predeterminedspeed.

13. In combination with means, located at spaced points along a trafficlane, and dividing said lane into a series of contiguous zones, andresponsive to vehicular movement along said lane, electric means locatedat a central station controlled by said flrst means for indicating inwhich of said zones speed of vehicular tramc is below a predeterminedspeed, and means to indicate the density of vehicular traflic in anyzone along said lane.

14. In combination with means, located at spaced points along a tramclane, dividing'said lane into a series of contiguous zones, andresponsive to vehicular movement along said lane,

electric means located at a central station, controlled by said firstmeans for indicating in which of said zones speed of vehicular tramc isbelow a predetermined speed, and electrically controlled traiilcsignalling means controlled by said vehicle responsive means to signalgo" to traffic in said lane when trafllc is moving above saidpredetermined speed, and to signal stop" in any zone where speed isreduced to below said predetermined speed and to signal "stop in allzones back of said last zone.

15. In combination with means, located at spaced points along a tramclane, dividing said lane into a series of contiguous zones, andresponsive to vehicular movement along said lane, electric means locatedat a central station controlled by said first means for indicating inwhich oi said zones speed or vehicular trailic is below a predeterminedspeed, and means to indicate the density oi vehicular trafilc in anyzone along said lane, and electrically operated trafiic signalling meanscontrolled by said vehicle responsive means to signal "go to traflic insaid lane when trafiic i moving above said predetermined speed, and tosignal stop in any zone where speed is reduced to below saidpredetermined speed and to signal stop" in all zones back of said lastzone.

16. In combination with means, located at spaced points along a tramclane, dividing said lane into a series of contiguous zones, andresponsive to vehicular movement along said lane, electric meanscontrolled by said first means for indicating it speed of vehiculartrafllc in any zone along said lane is below a predetermined speed, andmeans located at a central station and controlled by said first means.to indicate in which zone along said lane the traflic has slowed downbelow said predetermined speed.

17. In combination with means, located at spaced points along a tramclane, dividing said lane into a series of contiguous zones andresponsive to vehicular movement along said lane, electric meanscontrolled by said first means to indicate if vehicular movement in anyzone along said lane is above a predetermined speed, and electric meanslocated at a central station controlled by said first means to indicatein which zone along said lane, the traiilc has increased above saidpredetermined speed.

18-. In combination with means, located at spaced points along a traiilclane, dividing said lane into a series of contiguous zones, andresponsive to vehicular movement along said lane, electric means locatedat a central station and controlled by said first means for indicatingin which zone speed of vehicular trafilc along said lane is below apredetermined speed, and elec-- tric means located at said station andcontrolled by said first means to indicate in which zone fiow of tramcon said lane is above another higher predetermined speed,

19. In an automatic trafllc control system, a plurality of switchesdisposed at spaced intervals along the lane of a highway, dividing saidlane into a series of contiguous sections and adapted to be successivelyactuated by vehicles passing along said lane, a signalling deviceassociated with each section and means controlled by passage of avehicle over a section of said lane in less than a predetermined time,to actuate the signalling device associated with a succeeding section, aremote control panel, and means thereon to concurrently indicate whichsignaling device has been actuated.

20. Incombination, a plurality of vehicle ac tuated means disposed atspaced intervals along the lane of a highway dividing the highway into aplurality of successive sections, a difleren'tial mechanism for eachsection controlled by the actuations of the vehicle actuated meansbounding said sections, toindicate the number of vehicles in saidsection, a time delay relay for each section, means controlled by theactuation of a differential mechanism of one section to actuate the timedelay relay oi that section only when the differential mechanism oi thenext succeeding section is not operated after actuation of the precedingmechanism within the time set on said time delay relay, a go signal,normally operative, in each section, a stop signal in each section, andmeans controlled by the time delay relay in a section to extinguish thego" signal and operate the stop" signal in said section upon actuationof said time delay relay.

21. In combination, a plurality of vehicle actuated means disposed atspaced intervals along the lane of a highway dividing the highway into aplurality of successive sections, a differential mechanism for eachsection controlled by the actuations of the vehicle actuated meansbounding said sections, to indicate the number of vehicles in saidsection, a time delay relay for each section, means controlled by theactuation of a diiierential mechanism of one section to actuate the timedelay relay of that section only when the differential mechanism of thenext succeeding section is not operated after actuation of the precedingmechanism within the time set on said time delay relay, a "go signal,normally operative, in each section, a stop signal in each section,means controlled by the time delay relay in a section to extinguish thego signal and operate the stop" signal in said section upon actuation ofsaid time delay relay, and means to extinguish the go signals andoperate the stop" signals oi! the preceding sections of the highway uponoperation of the "stop signal in any section.

22. In combination, a plurality of vehicle actuated means disposed atspaced intervals along the lane of a highway dividing the highway into aplurality of successive sections, a differential mechanism for eachsection controlled by the actuations oi the vehicle actuated meansbounding said sections, to indicate the number of vehicles in saidsection, a time delay relay for each section, means controlled by theactuation of a diflerential mechanism of one section to actuate the timedelay relay of that section only when the differential mechanism 01' thenext succeeding section is not operated after actuation of the precedingmechanism within the time set on said time delay relay, a go" signal,normally operative, in each section, a stop" signal in each section,means controlled by the time delay relay in a section to extinguish thego" signal and operate the stop signal in said section upon actuation ofsaid time delay relay, means to extinguish the go" signals and operate'the stop" signals of the preceding sections of the highway uponoperation oi! the stop" signal in any section, a remote control panel,signal means on said panel for each of said sections, the meanscontrolled by said time delay relay of a section being adapted toactuate the signal means on said panel for said section, when the go"signal in said section is extinguished and the stop signal operated,

23. In combination, a plurality of vehicle actuated means disposed atspaced intervals along the lane of a highway dividing the highway into aplurality of successive sections, a difierential mechanism for eachsection'controlled by the actuations of the vehicle actuated meansbounding said sections, to indicate the number of vehicles in saidsection, a time delay relay for each section, means controlled by theactuation of a differential mechanism of one section to actuate the timedelay relay of that section only when the differential mechanism of thenext succeeding section is not operatedafter actuation of the precedingmechanism within the time set on said time delay relay, a "go" signalnormally operative, in each section, a stop" signal in each section,means controlled by the time delay relay in a section to extinguish thego signal and operate the stop signal in said section upon actuation ofsaid time delay relay, a remote control panel, signal means on saidpanel for each of said sections, the means controlled by said time delayrelay of a section being adapted to actuate the signal means on saidpanel for said section, when the go signal in said section isextinguished and the stop signal operated.

24. In combination, a plurality of vehicle actuated means disposed atspaced intervals along the lane of a highway dividing the highway into aplurality of successive sections, a differential mechanism for eachsection controlled by the actuations of the vehicle actuated meansbounding said sections, to indicate the number of vehicles in saidsection, a time delay relay for each of said sections, means controlledby the actuations of a differential mechanism of one section to actuatethe time delay relay of that section, a second time delay relay for eachof said sections, means to actuate the second time delay relay of asection upon actuation of its corresponding first time delay relay andof the succeeding section's differential mechanism before the time seton said first time delay relay, a "caution" signal for each sectionexcept the first section, and means to actuate the caution" signal of asucceeding section upon actuation of the second time delay relay oi apreceding section.

25. In combination, a plurality of vehicle actuated means disposed atspaced intervals along the lane of a highway dividing the highway into aplurality of successive sections, a diflerential mechanism for eachsection controlled by the actuations of the vehicle actuated meansbounding said sections, to indicate the number of vehicles in saidsection, a time delay relay for each of said sections, means controlledby the actuations of a differential mechanism of one section to actuatethe time delay relay of that section, a second time delay relay for eachof said sections, means to actuate the second time delay relay of asection upon actuation of its corresponding first time delay relay andof the succeeding section's diflerential mechanism before the time seton said first time delay relay, a caution signal for each section exceptthe first section, means to actuate the caution" signal of a succeedingsection upon actuation of the second time delay relay of a precedingsection, a remote control panel, Sig-- tuated means disposed at spacedintervals along the lane of a highway dividing, the highway into aplurality of successive sections, a diflerential mechanism for eachsection controlled by the actuations of the vehicle actuated meansbounding said sections, to indicate the number oi vehicles in saidsection, a time delay relay for each of said sections, means controlledby the differential mechanism 01' each section to actuate the time delayrelay of said section, a second time delay relay for each of saidsections, means to actuate each second time delay relay upon actuationof the corresponding first time delay relay and of the succeedingsection's differential mechanism before the time set on said first timedelay relay, a caution signal for each section except the first section,means to actuate the caution signal of a succeeding section uponactuation of the second time delay relay of a preceding section, a thirdtime delay relay for each section, means controlled by the diflerentialmechanism of one section to actuate the third time delay relay of thatsection only when the differential mechanism of the next succeedingsection is not operated within the time set on said third time delayrelay, a go signal, normally operative, in each section, a stop signalin each section, and means controlled by the third time delay relay ofany section to extinguish the "go signal of the same section and operatethe stop" signal in said section upon actuation of the third time delayrelay of said section.

27. In combination, a plurality of vehicle actuated means disposed atspaced intervals along the lane of a highway dividing the highway into aplurality of successive sections, a differential mechanism for eachsection controlled by the actuations of the vehicle actuated meansbounding said sections, to indicate the number of vehicle in saidsection, a time delay relay for each of said sections, means controlledby the diflerential mechanism of each section to actuate the time delayrelay of said section, a second time delay relay ior'each of saidsections, means to actuate each second time delay relay upon actuationof the corresponding first time delay relay and of the succeedingsections diflerential mechanism before the time set on said first timedelay relay, a caution signal for each section except the first section,means to actuate the caution signal of a succeeding section uponactuation of the second time delay relay of a preceding section, a thirdtime delay relay for each section, means controlled by the difierentialmechanism oi? one section to actuate the third time delay relay of thatsection only when the differential mechanism of the next succeedingsection is not operated within the time set on said third time delay, ago signal, normally operative, in each section, a stop signal in eachsection, means controlled by the third time delay relay of any sectionto extinguish the signal of the same section and operate the stop signalin said section upon actuation of the third time delay relay of saidsection, and means to extinguish the go signals and operate the stopsignals of the preceding sections of the highway upon operation of thestop signal in any section.

28. In combination, a plurality of vehicle actuated means disposed atspaced intervals along the lane of a highway dividing the highway into aplurality of successive sections, a difierential mechanism for eachsection controlled by the actuations of the vehicle actuated meansbounding said sections, to indicate the number of vehicles in saidsection, a time delay relay for each of said sections, means controlledby the difierential mechanism of each section to actuate the time delayrelay of said section, a second time delay relay for each of saidsections, means to actuate each second time delay relay upon actuationof the corresponding first time delay relay and of the succeedingsection's differential mechanism before the time set on said first timedelay relay, a caution signal for each section except the first section,means to actuate the "caution" signal of a succeeding section uponactuation ,oi. the second time delay relay or a preceding section, athird time delay relay for each section, means controlled by thediflerential mechanism of one section to actuate the third time delayrelay of that section only when the difierential mechanism oi the nextsucceeding section is not operated within the time set on said thirdtime delay relay, a "go" signal, normally operative, in each section, astop signal in each section, means controlled by the third time delayrelay 01' an section to extinguish the "go" signal of the same sectionand operate the "stop signal in said section upon actuation of the thirdtime delay relay of said section, means to extinguish the "go" signalsand operate the stop signals of the preceding sections of the highwayupon operation of the stop signal in any section, a remote controlpanel, signal means on said panel for each of said sections, said meanscontrolled by the third time delay relay of any section including meansfor actuating the signal means on said panel of said section, when thego signal insaid section is extinguished and the stop signal of saidsection operated.

29. In combination, a plurality of vehicle actuated means disposed atspaced intervals along the lane of a highway dividing the highway into aplurality of successive sections, a difi'erential mechanism for eachsection controlled by the actuations oi the vehicle actuated meansbounding said sections, to indicate the number 0! vehicles in saidsection, a time delay relay for each 0! said sections, means controlledby the differential mechanism of each section to actuate the time delayrelay of said section, a second time delay relay for each of saidsections, means to actuate each second time delay relay upon actuationof the corresponding first time delay relay and of the succeedingsection's diflerential mechanism before the time set on said first timedelay relay, a caution" signal for each section except the firstsection, means to actuate the caution signal of a succeeding sectionupon actuation of the second time delay relay oi a preceding section, athird time delay relay for each section, means controlled by thedifferential mechanism of one section to actuate the third time delayrelay of that section only when the differential mechanism of the nextsucceeding section is not operated within the time set on said thirdtime delay relay, a "go signal, normally operative, in each section, a"stop signal in each section, means controlled by the third time delayrelay of any section to extinguish the upon actuation oi the "caution"signal in said section.

30. In combination, a plurality of vehicle actuated means disposed atspaced intervals along the lane of a highway dividing the highway into aplurality of successive sections, a difierential mechanism for eachsection controlled by the actuations oi the vehicle actuated meansbounding said sections, to indicate the number- 0!. vehicles in saidsection, a time delay relay for each of said sections, means controlledby the dinerential mechanism of each section to actuate the timedelayrelay of said section, a second time delay relay for each of saidsections, means to actuate each second time delay relay upon actuationof the corresponding first time delay relay and of the succeedingsection's diflerential mechanism before the time set on said first timedelay relay, a caution" signal for each section except the firstsection, means to actuate the caution" signal of a succeeding sectionupon actuation of the second time delay relay oi a preceding section, athird time delay relay for each section, means controlled by thedifierential mechanism of one section to actuate the third time delayrelay of that section only when the differential mechanism of the nextsucceeding section is not operated within the time set on said thirdtime delay relay, a go" signal, normally operative, in each section, a"stop" signal in each section, means controlled by the third time delayrelayoi any section to extinguish the go" signal of the same section andoperate the stop" signal in said section upon actuation of the thirdtime delay relay of said section, a remote control panel, signal meanson said panel for each of said sections, said means controlled by thethird time delay relay of any section including means for actuating thesignal means on said panel of said section, when the "go" signal in saidsection is extinguished and the "stop" signal oi said section operated.

31. In combination, a plurality oi vehicle actuated means disposed atspaced intervals along the lane of a highway dividing the highway into aplurality of successive sections, a differential mechanism for eachsection controlled by the actuations of the vehicle actuated meansbounding said sections, to indicate the number 0! vehicles in saidsection, a time delay relay for each of said sections, means controlledby the dinerential mechanism of each section to actuate the time delayrelay of said section, a second time delay relay for each of saidsections, means to actuate each second time delay relay upon actuationoi. the corresponding first time delay relay and of the succeedingsections difierential mechanism before the time set on said first timedelay relay, a "caution signal foreach section except the first section,means to actuate the caution" signal or a succeeding section uponactuation of the second time delay relay 0! a preceding section, a thirdtime delay relay for each section, means controlled by the diiiferentialmechanism oi. one section to actuate the third time delay relay of thatsection only when the difierential mechanismpt the next succeedingsection is not operated within the time set on said third time delayrelay, a "go signal, normally operative, in each section, a stop" signalin each section, means controlled by the third time delay relay of anysection to extinguish the go" signal of the same section and operate the"stop signal in said section upon actuation oi! the third time delayrelay of said section, a remote control panel, signal means on saidpanel for each of said sections, said means controlled by the'third timedelay relay of any section including means for actuating the signalmeans on said panel of said section, when the "go signal in said sectionis extinguished and the stop signal of said section operated, a secondsignal means on said panel for each section except the first section andmeans to operate said second panel signal means of a section uponactuation of the "caution signal in said section.

32. In combination, a plurality of vehicle actuated means disposedat-spaced intervals along the lane of a highway dividing the lane into aplurality of successive sections, a "go signal, normally operative, foreach section, a stop signal for each section, an electrical circuitinterconnecting said vehicle actuating means and said signals, saidcircuit including a delayed time relay for each section, meanscontrolled by the vehicle actuated means at the entrance of a'section toactuate the time delay relay 0! said section when the vehicle actuatedmeans at the exit of said section is not actuated atter actuation of theentrance means within the time set on said time delay relay, and meanscontrolled by said time delay relay to extinguish the go" signal of saidsection and operate said stop signal upon actuation of said time delayrelay.

33. In combination, a piurality'of vehicle actuated means disposed atspaced intervals along the lane of a highway'dividing the lane into aplurality of successive sections, a "go signal, normally operative, foreach section, a stop" signal for each section, an electrical circuitinterconnecting said vehicle actuating means and said signals, saidcircuit including a delayed time relay for each section, meanscontrolled by the vehicle actuated means at the entrance of a sec-- tionto actuate the time delay relay oi! said section when the vehicleactuated means at the exit of said section is not actuated afteractuation of the entrance means within the time set on said time delayrelay, means controlled by said time delay relay to extinguish thego'signal of'said section and operate said stop" signal upon actuationof said time delay relay, and meansto extinguish the "go signals andoperate the stop signals of the preceding sections of the highway uponoperation of the stop signal in any section. A 34. In combination, aplurality of vehicle actuated means disposed at spaced intervals alongthe lane of a highway dividing the lane into a plurality of successivesections, a go signal, normally operative, for each section, a stopsignal for each section, an electrical circuit interconnecting saidvehicle actuating means and said signals, said circuit including adelayed time relay for each section, means controlled by thevehicle-actuated means at the entrance of a section to actuate the timedelay relay 0! said section when the vehicle actuated means 'at the exitof said section is not actuated after actuation of the entrance meanswithin the time set on said time delay relay, means controlled by saidtime delay relay to extinguish the go" signal 0! said section andoperate said stop signal upon actuation of said time delay relay, andmeans to extinguish the go" signals and operate the stop" signals of thepreceding sections oi the highway upon operation 7 of the stop signal inany section, a remote control panel, signal means on said panel for eachof said sections, the means controlled by said time delay r'elayincluding means for actuating said signal means on said'panel of onesection, when the-go" signal in said section is extinguished and thestop signal or said section operated.

35. In combination, a plurality of vehicle actuated means disposed atspaced intervals along the lane of a highway dividing the highway into aplurality of successive sections, a time delay relay for each section,means controlled by the actuation of the vehicle actuated means at theentrance of each section to actuate the time delay relay'ot saidsection, a second time delay relay for each section, means to actuatethe second time delay relay of a section upon actuation of the firsttime delay relay of said section and of the vehicle actuated-meanslocated at the exit of a section after actuation of the entrance meansbefore the time set on said first time delay relay, .a caution signalfor each section except the first section, and means to actuate the"caution signal of a succeeding section upon actuation of the secondtime delay relay oi! a preceding section.

36. In combination, a plurality of vehicle actuated means disposed atspaced intervals along the lane of a highway dividing the highway into aplurality of successive sections, a time delay relay for each section,means controlled by the actuation of the vehicle actuated means at theentrance of each section to actuate the time delay relay of saidsection, a second time delay relay for each section, means to actuatethe second time delay relay 01' a section upon actuation of the firsttime delay relay of said section and or the vehicle actuated meanslocated at the exit of a section after actuation of the entrance meansbefore the time set on said first time delay relay, a caution" signalfor each section except the first section, means to actuate the caution"signal of a succeeding section upon actuation of the second time delayrelay of a preceding section, a remote control panel, signal means onsaid panel for each section except the first section, and means tooperate the panel signal means of a section upon actuation of the"caution signal in said section.

BENJAMIN COOPER.

